Heating, ventilation, and air conditioning (HVAC) systems generally operate to provide optimal indoor air quality to occupants within interior building spaces. HVAC systems achieve optimal indoor air quality by conditioning air, removing particle contaminants by way of ventilation and filtration of air, and providing proper building pressurization.
While there are many different HVAC system designs and operational approaches, and each building design is unique, HVAC systems generally share a few basic design elements. For example, outside air (“supply air”) generally is drawn into a HVAC system of a building through an air intake. Once in the HVAC system, the supply air is filtered to remove particle contaminants, then heated or cooled, and then circulated throughout the building by way of an air distribution system. Many air distribution systems comprise a return air system configured to draw air from interior building spaces and return the air (“return air”) to the HVAC system. The return air is then mixed with supply air and then filtered, conditioned, and circulated throughout the building. Often times, a portion of the air circulating within the building may be exhausted to the exterior of the building so as to maintain a desired barometric pressure within the building.
As will be appreciated, the effectiveness of the HVAC system to provided an optimal indoor air quality depends largely on an ability of an air filter within the HVAC system to remove particle contaminants from the air within the building. A HVAC system air filter typically comprises fibrous materials configured to remove solid particulates, such as dust, pollen, mold, and bacteria from the air passing through the HVAC system. A drawback to conventional HVAC system air filters, however, is that highly effective air filters capable of removing very small contaminants, such as airborne molecular contaminants and volatile organic compounds (VOCs), tend to restrict airflow through the air filter, thereby making the HVAC system work harder and consume more energy.
Another drawback to conventional HVAC system air filters is that dirty or clogged air filters typically are removed from the HVAC system and discarded, and a new HVAC system air filter is then installed. Further, HVAC system air filters may be unnecessarily discarded and replaced in an effort to increase HVAC system airflow and thus decrease operation costs. Considering that there are millions of buildings with HVAC systems throughout the world, the volume of discarded air filters that could be eliminated from landfills is a staggering number. What is needed, therefore, is a HVAC system air filter which may be periodically cleaned and reused, and is configured for removing airborne molecular contaminants and VOCs without obstructing air flow through HVAC systems.